Linear RF polar modulated SiGe Class E and F power amplifiers

Abstract

Two fully-integrated linearized polar modulated class E and F power amplifiers (PA) with switch-mode supply modulation are presented. The PAs are implemented in a 0.18mum SiGe BiCMOS process and can be used to transmit varying envelope RF signals operating at 870-920MHz. The class E PA gives a peak output power of 26.4dBm and a maximum efficiency of 62%. The class F PA gives peak output power of 23dBm with 53 % drain efficiency. When using delta modulation to control the switch-mode supply, the class F and E polar amplifiers give ACPRs for an EDGE input waveform (at 400kHz offset) of -46dBc and -37.7dBc respectively